RT Book, Section
A1 Gertz, Morie A.
A1 Sher, Taimur
A1 Dispenzieri, Angela
A1 Buadi, Francis K.
A2 Kaushansky, Kenneth
A2 Lichtman, Marshall A.
A2 Prchal, Josef T.
A2 Levi, Marcel M.
A2 Press, Oliver W.
A2 Burns, Linda J.
A2 Caligiuri, Michael
SR Print(0)
ID 1121101404
T1 Immunoglobulin Light-Chain Amyloidosis
T2 Williams Hematology, 9e
YR 2015
FD 2015
PB McGraw-Hill Education
PP New York, NY
SN 9780071833004
LK accessmedicine.mhmedical.com/content.aspx?aid=1121101404
RD 2024/04/20
AB SUMMARYAmyloidosis  should  be  considered  in  any  patient  presenting  with  nephrotic  range  proteinuria;  infiltrative  cardiomyopathy  or  heart  failure  with  preserved  ejection  fraction;  hepatomegaly  without  specific  imaging  findings;  or  peripheral  neuropathy,  particularly  if  a  monoclonal  protein  is  present;  as  well  as  any  patient  with  atypical  multiple  myeloma.When  a  patient  is  seen  with  a  relevant  syndrome,  the  patient  should  have  immunofixation  of  serum  and  urine  proteins  and  measurement  of  κ  and  λ  immunoglobulin  free  light  chains.  If  all  of  these  tests  are  normal,  it  is  unlikely  that  the  patient  has  immunoglobulin  light-chain  (AL)  amyloidosis.If  any  of  the  above  tests  are  positive,  further  investigation  for  amyloidosis  should  be  undertaken.  The  diagnostic  test  of  choice  is  subcutaneous  fat  aspiration;  marrow  biopsy  is  the  second  best  procedure.  With  these  two  tests,  83  percent  of  patients  will  have  a  positive  result  when  stained  with  Congo  red  under  green  birefringence.All  patients  with  biopsy  proven  amyloidosis  should  have  the  deposits  analyzed  by  laser  capture  microdissection  mass  spectroscopy  to  definitively  classify  the  exact  protein  subunit  composing  the  amyloid.  This  technique  does  not  distinguish  between  systemic  and  localized  amyloidosis,  however.The  prognosis  in  AL  amyloidosis  is  determined  by  three  tests:  (1)  the  N-terminal  probrain  natriuretic  peptide,  (2)  serum  troponin,  and  (3)  the  difference  between  the  involved  and  uninvolved  immunoglobulin  free  light  chains.  These  three  tests  can  be  combined  to  stage  the  patient  from  stage  1  through  stage  4.Treatment  of  AL  amyloidosis  involves  either  standard  systemic  chemotherapy  or  high-dose  chemotherapy  with  autologous  stem  cell  transplantation.  Fit  patients  who  are  expected  to  have  low  morbidity  with  transplantation  should  undergo  this  approach.  The  majority  of  patients,  however,  will  not  be  candidates  for  transplantation  and  should  be  treated  with  traditional  systemic  chemotherapy;  with  the  cyclophosphamide,  bortezomib,  and  dexamethasone  regimen  currently  favored  by  many  investigators.